Portable machining device

ABSTRACT

A communication adapter 31 for conducting radio communication between a portable machining device 1 and a dust collector 40, such that the dust collector 40 may operate synchronously with the portable machining device 1 with respect to a start/stop operation when performing a cutting task is detachably incorporated in a handle 20 of the portable machining device 1. Because of this arrangement, a high level of dust-proof ability as well as ease of maneuverability in attaching and detaching the communication adapter 31 can be achieved.

CROSS-REFERENCE

This is a Divisional Application of application Ser. No. 15/921,078,filed Mar. 14, 2018, which in turn claims priority to Japanese patentapplication serial number 2017-075524, filed on Apr. 5, 2017, thecontents of which are incorporated herein by reference in theirentirety.

TECHNICAL FIELD

The present disclosure generally relates to a portable machining deviceand/or a portable machining tool such as, for example, a portablecutting device used for cutting a material to be cut (workpiece) such aswooden material, etc.

BACKGROUND ART

A conventional portable machining device generally includes, forexample, a base that contacts an upper surface of the workpiece, as wellas a machining device main body that is supported on an upper surfaceside of the base so as to be movable in an up-to-down direction. Themachining device generally includes an electric motor, as well as acutting blade that can be rotatably driven with the electric motorserving as a driving force. By moving the machining device main body inthe up-to-down direction with respect to the base, the machining devicecan be positioned between a cutting position in which the cutting bladeprotrudes below a lower surface of the base and a retreat position inwhich the cutting blade retreats in the upward direction with respect tothe lower surface of the base. With the rotation of the cutting bladethat protrudes below the lower surface of the base and the movement ofthe machining device with respect to the workpiece, a cutting task canbe performed. A cutting blade cover that covers approximately thecircumferential periphery of the cutting blade may be provided on theupper surface of the base. An exposed lower portion of the cutting bladethat protrudes in the downward direction from the cutting blade covercan cut into the workpiece. The upper periphery of the blade in thecutting position can be covered by the cutting blade cover, whichprevents cutting dust from scattering around.

In some types of portable machining devices developed in the past, adust collector for collecting cutting dust generated by a cutting taskis used as an incidental device. For example, Japanese Laid-Open PatentPublication No. 2004-195565 discloses a portable machining devicerelating to a dust collector serving as the incidental device, in whichradio communication can be conducted between the portable machiningdevice and the dust collector, where said communication can beautomatically stopped by a stop operation of the portable machiningdevice.

However, in the portable machining device disclosed in theabove-discussed patent Publication, a communication adapter used inconducting radio communication is exposed to the outside. As a result,the dustproof ability of the device against cutting dust issubstantially inadequate and is a deficiency in need of improvement.

Thus, as a result of the mentioned deficiencies in the art, there is aneed to improve the extent to which the communication adapter in theportable machining device is dustproof, where said device includes thecommunication adapter for conducting radio communication between theportable machining device and the incidental device such as the dustcollector.

SUMMARY

In one exemplary embodiment of the present disclosure, a portablemachining device comprises a base with which a material to be cut isbrought into contact, a machining device main body that is supportedabove an upper surface of the base, and a handle that is formedintegrally with the machining device main body. Furthermore, themachining device main body includes a rotary cutting blade that isrotated by an electric motor serving as a drive source, the cuttingblade being able to protrude below a lower surface of the base such thata protruding portion of the cutting blade can perform a cutting task bycutting into a material to be cut. Furthermore, an adapter forconducting radio communication with an incidental device of the portablemachining device is detachably provided in the interior of the machiningmain body, and the incidental device is started and stopped in asynchronous manner with the corresponding start and stop operations ofthe portable machining device.

According to the embodiment, the adapter for conducting radiocommunication is provided in the interior of the machining device mainbody. Because it is provided in the interior, the dustproof ability ofthe adapter can be substantially increased as compared to the case wherethe adapter is outside. Furthermore, the adapter is removably attachedto the machining device main body, and accordingly in a case where theradio communication is not performed, the adapter can be easily removedfrom the machining device, and can be used in another device. In thisrespect, usability as well as versatility of the adapter and byconsequence that of the radio communication function and the portablemachining device as a whole can be improved.

In another exemplary embodiment of the disclosure, the adapter forconducting radio communication is disposed above the electric motor.

According to such an embodiment, information about the start/stop statusof the electric motor etc. can be accurately transmitted to the adapterand thus reliability of the radio communication function can beimproved.

In another exemplary embodiment of the disclosure, the adapter forconducting radio communication may be removed from the device main bodyby moving the adapter in a direction away from the cutting blade.

According to such an embodiment, removing and attaching operability ofthe adapter can be improved.

In another exemplary embodiment of the disclosure, the adapter forconducting radio communication is disposed at a front portion of thehandle.

According to such an embodiment, the maneuverability and ease of use inremoving and attaching the adapter can be furthermore improved.

In another exemplary embodiment of the disclosure, a controller forcontrolling radio communication is disposed over the electric motor.

According to such an embodiment, by being placed over the motor, thedustproof ability and cooling ability with respect to the controller canbe established to the same level as the electric motor.

In another exemplary embodiment of the disclosure, the adapter isdisposed at a lateral side of the handle on a side of the motor so as tobe close in a direction right above the electric motor.

According to such an embodiment, since the adapter for conducting radiocommunication is disposed in the vicinity above and immediatelyproximate to the electric motor, information on the start/stop status ofthe electric motor etc. can be accurately transmitted to the incidentaldevice and thus reliability of the radio communication function can beimproved.

In another exemplary embodiment of the disclosure, a controller forcontrolling the radio communication is housed at the rear of the handle.

According to such an embodiment, the controller can be arranged in acompact manner by, for example, utilizing a battery attachment portion,as well as providing a substantially dustproof environment for thecontroller.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an overall perspective view of a portable machining deviceaccording to an exemplary embodiment (first embodiment) of the presentdisclosure, seen from a rear upper left.

FIG. 2 is a right side view of the portable machining device accordingto the exemplary embodiment (first embodiment).

FIG. 3 is a left side view of the portable machining device according tothe exemplary embodiment (first embodiment).

FIG. 4 is an overall plan view of the portable machining deviceaccording to the exemplary embodiment (first embodiment).

FIG. 5 is an overall lateral cross-sectional view of the portablemachining device according to the exemplary embodiment (firstembodiment).

FIG. 6 is a right side view of a portable machining device according toanother exemplary embodiment (second embodiment).

FIG. 7 is an overall perspective view of the portable machining deviceaccording to another embodiment (second embodiment), seen from a upperleft.

FIG. 8 is a left side view of the portable machining device according toanother embodiment (second embodiment).

FIG. 9 is a longitudinal cross-sectional view of the portable machiningdevice according to another embodiment (second embodiment), seen from arear side.

FIG. 10 is a rear side view of a portable machining device according toanother exemplary embodiment (second embodiment).

FIG. 11 is a left side view of the portable machining device accordingto another embodiment (second embodiment), showing a state where amachining device main body is situated at an upper end position.

FIG. 12 is an overall perspective view of the portable machining deviceaccording to another embodiment (second embodiment), seen from a rearupper left. This figure shows that a left half-split housing of a handleas well as that of a controller housing is removed.

FIG. 13 is a rear side view of the portable machining device accordingto another embodiment (second embodiment), showing a machining main bodyis moved to a lower end position and an upper portion thereof is tiltedin a rightward direction.

FIG. 14 is a schematic side view of a portable machining device and anincidental device according to another exemplary embodiment (fourthembodiment), showing two portable machining devices.

DETAILED DESCRIPTION

The detailed description set forth below, when considered with theappended drawings, is intended to be a description of exemplaryembodiments of the present invention and is not intended to berestrictive and/or to represent the only embodiments in which thepresent invention can be practiced. The term “exemplary” used throughoutthis description means “serving as an example, instance, orillustration,” and should not necessarily be construed as preferred oradvantageous over other exemplary embodiments. The detailed descriptionincludes specific details for the purpose of providing a thoroughunderstanding of the exemplary embodiments of the invention. It will beapparent to those skilled in the art that the exemplary embodiments ofthe invention may be practiced without these specific details. In someinstances, these specific details refer to well-known structures,components and/or devices that are shown in block diagram form in orderto avoid obscuring significant aspects of the exemplary embodimentspresented herein.

Representative, non-limiting embodiments according to the presentdisclosures will be described with reference to FIGS. 1 to 14. FIGS. 1to 5 show a first embodiment of the present disclosure. In the firstembodiment, a cutting device (circular saw) that a user can hold andmove in a cutting proceeding direction for perform a cutting task isexemplified as an example of a portable machining device 1. In thefollowing embodiments, the front and rear directions of members andconfigurations are based relative to the cutting proceeding direction asdescribed above. The user may be situated on the rear side of theportable machining device 1, wherein the leftward and rightward aredetermined based on the user's position.

Generally, the portable machining device 1 may be provided with a base 2that is brought into contact with a material to be cut (workpiece) W aswell as a machining device main body 10 that is supported above an uppersurface of the base 2. The base 2 may have an approximately rectangularflat-plate shape. A lower surface of the base 2 on its underside may bea contact surface 2 a that is brought into contact with the workpiece W.The machining device main body 10 may be supported on the upper surfaceside of the base 2 so as to be swingable in the up-to-down direction. Asshown in FIG. 2, the machining device main body 10 may be supported onthe front side of the base 2 so as to be swingable in the up-to-downdirection about a main body support shaft 19. Furthermore, the machiningdevice main body 10 may also be supported such that it can be tilted inthe left-to right direction via a front support portion 25 and a rearsupport portion 26. By changing the up-to-down position of the machiningdevice main body 10 that is swung about the main body support shaft 19,the protruding length of a cutting blade 11 that protrudes below thelower surface of the base 2 can be adjusted. Because of thisconfiguration, the cutting depth of the cutting blade 11 with respect tothe workpiece W can be changed. Furthermore, by tilting the machiningdevice main body 10 in the leftward or rightward direction via the frontsupport portion 25 and the rear support portion 26, the cutting blade 11can be used to perform an oblique cat into the workpiece W.

A cutting blade cover 14 may cover approximately the upper semi-circularhalf of the circumference of the cutting blade 11. Cutting dustgenerated by the cutting task of the workpiece W may be mostly blown outwithin the cutting blade cover 14. As shown in FIG. 2, an arrow 14 aindicating the rotational direction of the cutting blade 11 is labeledon the right side of the cutting blade cover 14. Referring to FIG. 2, byrotation of the cutting blade 11 in the counterclockwise direction asindicated by arrow 14 a, cutting dust may be blown out at the front sideof the cutting blade cover 14. Cutting dust that is blown out in thismanner may flow to the rear side of the cutting dust cover 14 along withairflow generated by rotation of the cutting blade 11. As shown in FIG.1, a dust collection hose 41 of a dust collector 40 can be connected toa dust collection port 20 a in place of a dust collection bag or a dustcollection box.

A movable cover 4 may cover approximately the lower semi-circular halfof the circumference of the cutting blade 11. The movable cover 4 may besupported so as to be opened/closed along the outer circumferentialperiphery of the cutting blade 11. As shown in the figures, the movablecover 4 may be brought into contact with, for example, an end of theworkpiece W to relatively rotate in an opening clockwise direction, whenthe device progresses frontwards against the workpiece W.

As shown in FIG. 5, an electric motor 12 may be joined to the leftsurface side of the cutting blade cover 14 while a reduction gearportion 13 is disposed in between the electric motor 12 and the cuttingblade cover 14 in the left-to-right direction. The electric motor 12 maybe provided with a stator 12 b that is fixed to a motor case 12 a aswell as a rotor 12 c that is rotatably supported on an innercircumference side of the stator 12 b via a motor shaft 12 d. Rotationpower of the electric motor 12 may be output to a spindle 3 via thereduction gear portion 13. The spindle 3 may protrude into an inner sideof the cutting blade cover 14 and the circular cutting blade 11 may bescrew-fixed to said inner protruding portion of the spindle 3.

A cooling fan 12 e may be attached to the motor shaft 12 d of theelectric motor 12. A plurality of intake holes 12 f may be provided onthe left surface of the motor case 12 a. When the electric motor 12 isdriven and the cooling fan 12 e rotates, outside air may be introducedinto the motor case 12 a via the intake holes 12 f. Outside air (motorcooling air) introduced into the motor case 12 a may flow in therightward direction, which can cool the stator 12 b and rotor 12 c, etc.

A controller housing 15 may be provided behind the electric motor 12.The controller housing 15 may house a controller 16 having a rectangularflat-plate shape. The controller 16 may house a control circuit board ina case having a shallow bottom and the interior of the case may be resinmolded. In this embodiment, the controller 16 may be housed in thecontroller housing 15 such that a width direction of the controller 16corresponds to the front-to-rear direction of the device and thecontroller 16 is disposed approximately in an erect manner in theup-to-down direction, as shown in FIG. 3. The controller 16 may includea control circuit for mainly controlling the electric motor 12 and apower supply circuit. In particular, the control circuit may include amicroprocessor that transmits a control signal based on positionalinformation of the rotor 12 c that is detected by a sensor PCB mountedon the electric motor 12. Furthermore, the controller 31 may alsoinclude a drive circuit composed of FETs that switches and/or adjuststhe current of the electric motor 12 based on the control signalreceived from the control circuit. Furthermore, the controller 31 mayalso include an auto-stop circuit that interrupts power supply to theelectric motor 12 based on a detection result from the battery pack 18in order to prevent over-discharging and current overload conditions.

The interior of the controller housing 15 may be in fluid communicationwith an interior of the motor case 12 a via a ventilation hole 12 g. Theventilation hole 12 g may be provided on a lateral side of the coolingfan 12 e. Because of this configuration, motor cooling air generated byrotation of the cooling fan 12 e may flow outwards from the motor case12 a into the controller housing 15 via the ventilation hole 12 g. Motorcooling air flowing into the control housing 15 may cool the controller16. After that, motor cooling air may be directed to the exterior of thecontroller housing 15 through an exhaust hole 15 a provided on the rightside of the controller housing 15.

A flat-plate shaped battery attachment portion 17 may be provided on therear side of the controller housing 15 so as to extend in the rearwarddirection. A battery pack 18 may be attached to a lower surface of thebattery attachment portion 17.

The battery pack 18 may be a lithium ion battery within which aplurality of battery cells may be incorporated in a battery case havingan approximately hexahedral shape. The battery pack 18 may be highlyversatile such that it can be attached to other power tools, serving asa power source for electric power tools other than the portablemachining device 1. FIG. 5 shows a cross-section of a battery pack 18.The battery pack 18 may be of a slide-attachment type and may beattached to the battery attachment portion 17 by being slid in therightward direction as shown by the void arrow of FIG. 1 depicting theattaching direction. Conversely, the battery pack 18 may be detachedfrom the battery attachment portion 17 by sliding the battery pack 18 inthe leftward direction while an unlock button 18 a for removal isconcomitantly pressed down. The detached battery pack 18 can be chargedby a dedicated battery charger, such that it can be repeatedly used.

A handle 20 that the user holds may be provided on an upper side of theelectric motor 12. The handle 20 may have a loop shape straddling theupper surface of the electric motor case 12 a as well as the uppersurface of the battery attachment portion 17. A switch lever 21 whichmay be pulled inwards by a user's fingertips may be provided on theinner circumference of the handle 20. Furthermore, a lock-off lever 22for locking the switch lever 21 to an off position may be provided abovethe switch lever 21. The lock-off lever 22 can be operated on both theleft side and the right side thereof. The switch lever 21 can be pulledwhile the lock-off lever 22 is simultaneously being pulled down by theuser's finger. In this manner, the lock-off lever 22 can prevent theswitch lever 21 from accidentally being pulled.

An erection portion 20 a may be provided at the front of the handle 20extending from the upper surface of the motor case 12 a of the electricmotor 12 in the upward direction. A radio communication unit 30 forconducting radio communication between the portable machining device 1and incidental devices may be provided on the left side of the erectionportion 20 a (towards the upper side of the electric motor 12), as shownin FIG. 1. Furthermore, as shown in FIG. 3, the radio communication unit30 may be situated over the electric motor 12 (approximately right abovethe electric motor), as viewed in a direction of the left-to-right motoraxis J, in the plane comprising the up-to-down and left-to-rightdirections, in a case where the machining device main body 10 is movedto a lower end position and the cutting depth of the cutting blade 11with respect to the workpiece W protruding below contact surface 2 a isset to its maximum. In this way, the radio communication unit 30 may bedisposed at a lateral side of the handle 20 on a side of the electricmotor 12 so as to be over the electric motor 12 or to be close in adirection right above the electric motor 12. In other words, the radiocommunication unit 30 may be disposed in the vicinity of and immediatelyproximate to the electric motor 12. In this embodiment, the radiocommunication unit 30 may be provided for conducting radio communicationbetween the portable machining device 1 and a dust collector 40 servingas the incidental device. By conducting radio communication between theportable machining device 1 and the dust collector 40 via the radiocommunication unit 30, the dust collector 40 may operate synchronouslywith the portable machining device 1 with regard to a start/stopoperation of the dust collector 40, etc.

The radio communication unit 30 may be provided with a communicationadapter 31. The communication adapter 31 may be inserted into an adapterinsertion portion 32 that is provided on the left side of the erectionportion 20 a. The adapter insertion portion 32 may be a rectangular holewith rounded edges formed deep into the interior of the handle 20 in therightward direction. Upon insertion of the communication adapter 31 intothe adapter insertion portion 32, the communication adapter 31 may beelectrically connected with a radio communication controller 34. Theradio communication controller 34 may be housed at an upper region inthe interior of the motor case 12 a. The adapter insertion portionopening 32 may be covered by a cap 33. By inserting the communicationadapter 31 into the adapter insertion portion 32 and thereafter closingthe cap 33, the communication adapter 31 and the adapter insertionportion 32 may be adequately covered and resistant to dust.

The communication adapter 31 may have been previously associated(paired) with a communication adapter of the specific dust collector 40such that the radio communication can be performed between the two, forexample before being inserted into adapter insertion portion 32. In astate where the communication adapter 31 is attached to the radiocommunication unit 30, when the switch lever 21 is switched on to run(start) the portable machining device 1, the start information of theportable machining device 1 may be transmitted to the dust collector 40,through radio communication conducted by communication adapter 31, basedon which the dust collector 40 may automatically run. As shown in FIG.1, by attaching the dust collection hose 41 to the dust collection port14 b, the dust collector 40 may be an incidental device of the portablemachining device 1, and the dust collector 40 may be in a standby statewhen powered on.

As discussed above, the portable machining device 1 may be provided withradio communication functionality to communicate with the dust collector40 as the incidental device with regard to start and stop operations,etc. Accordingly, the dust collector 40 may automatically start/stop inaccordance with a start/stop operation of the portable machining device1, which can furthermore improve operability, maneuverability, and easeof use of both the portable machining device 1 and the dust collector40.

According to the portable machining device 1 of the first embodiment asdiscussed above, the communication adapter 31, which is previouslyassociated (paired) with the dust collector 40 serving as the incidentaldevice with regard to the start/stop operation thereof, may beconfigured to be removably housed in the erection portion 20 a of thehandle 20. Because of this configuration, the dustproof ability as wellas convenience of the communication adapter 31 can be improved. Whenthere is no need to perform the radio communication with the dustcollector 40, the communication adapter 31 can be easily removed fromthe portable machining device 1. In this respect, communication adapter31 improves convenience for the user.

Furthermore, the radio communication unit 30 may be provided on the leftside of the erection portion 20 a (on a side of the electric motor 12)so as to be over the electric motor 12 or to be close in a directionright above the electric motor 12, i.e., so as to be disposed in thevicinity of and immediately proximate to the electric motor 12. Becauseof this configuration, information about start/stop status of theelectric motor 12 etc. can be accurately and rapidly communicatedbetween the dust collector 40 and the communication adapter 31 asopposed to the case where the radio communication unit is elsewhere anddoesn't receive the information properly. In this respect, reliabilityof the radio communication unit 30 is improved.

Furthermore, the communication adapter 31 may be configured to beremoved from the adapter insertion portion 32 by being moved away fromthe cutting blade 11 in the leftward direction as shown by the voidarrow showing the detaching direction in FIG. 1. Because of thisconfiguration, attaching and detaching operability of the communicationadapter 31 can be improved.

The embodiment discussed above may be further modified without departingfrom the scope and spirit of the present teachings. FIGS. 6 to 13 show aportable machining device 50 of another embodiment (second embodiment).As shown in FIGS. 6 to 9, the portable machining device 50 may bereferred to as a so-called plunge circular saw, which generally includesa base 52 that is brought into contact with an upper surface of aworkpiece W as well as a machining device main body 51 that is supportedon an upper surface side of the base 52. The base 52 may have anapproximately rectangular flat-plate shape. A lower surface of the base52 may be a contact surface 52 a that is brought into contact with theworkpiece W. A cutting blade cover 53 may be supported on an uppersurface side of the base 52. A front support portion 55 and a rearsupport portion 56 may be provided on the upper surface of the base 52at a forward position and a rearward position, respectively. The frontsupport portion 55 and the rear support portion 56 may be providedparallel to each other in an erected manner. The cutting blade cover 53may be supported so as to be tiltable in the left-to-right direction viathe front support portion 55 and the rear support portion 56.

A rear portion of the machining device main body 51 may be supported ona left side of the cutting blade cover 53 via a main body support shaft57 about which that the machining device main body 51 can be swung inthe up-to-down direction. The main body support shaft 57 may be disposedto the rear of the center of rotation, spindle 59 (see FIG. 5) of thecutting blade 54. Thus, the cutting blade 54 may be largely moved in theup-to-down direction within the cutting blade cover 53. The machiningdevice main body 51 may be biased to swing in an upward direction by acompression spring 67 that is interposed between the machining devicemain body 51 and the cutting blade cover 53. As shown in FIG. 11, themachining device main body 51 may be held at an upper end position(standby position) by the biasing force of the compression spring 67. Alower portion of the cutting blade 54 may protrude below a contactsurface 52 a of the base 52 in the downward direction when the machiningdevice main body 51 is swung about the main body support shaft 57 in thedownward direction against the biasing force of the compression spring67. FIG. 8 shows a state upon swinging the machining device main body 51in the downward direction, where the protruding length of the cuttingblade 54 below the contact surface 52 a of the base 52 reaches itsmaximum (where the machining device main body 51 reaches a lower endposition). By moving the portable machining device 50 in the forwarddirection while this lowermost protruding state of the cutting blade 54is being held, the cutting blade 54 can cut into the workpiece W fromthe blade's front end and a cutting task can be performed. Instead ofmoving in the forward direction, if the machining device main body 51 isswung in the downward direction while the cutting blade 54 rotates,driven by the driving force of the electric motor 60, the lower portionof the rotating cutting blade 54 may protrude below the contact surface52 a of the base 52 so as to enter downwards into the workpiece W whenperforming a cut, where said cut is referred to as a plunge cut.

The machining device main body 51 may be supported by the cutting bladecover 53 that in turn can be maneuvered to tilt in the left-to-rightdirection via the front support portion 55 and the rear support portion56. Because of this configuration, the cutting blade 54 within thecutting blade cover 53 can also consequently be tilted with respect tothe base 52 in the left-to-right direction. FIG. 13 shows a state wherethe machining device main body 51 is tilted in the rightward directionby approximately 45°. By tilting the cutting blade 54 in theleftward/rightward direction, the portable machining device 50 can beused to perform an oblique cut into the workpiece W (bevel cutting). Atilt angle of the cutting blade cover 53, and in turn that of thecutting blade 54 within the cutting blade cover 53 may be indicated andmeasured by lines demarcating angles on an angle scale provided on thefront support portion 55 (see FIG. 11). A tilt position of the cuttingblade cover 53, and by consequence that of the cutting blade 54, withrespect to the base 52 can be adjusted as desired to a particular angleby fastening the fixing screws 55 a, 56 a.

The cutting blade cover 53 may cover the upper region of the cuttingblade 54 above the contact surface 52 a, which prevents cutting dustfrom scattering. A dust collection port 53 a used for connecting a dustcollection hose or a dust collection box may be provided at the rear ofthe cutting blade cover 53. As a result, cutting dust blown out in theproximity of a cutting position (cut-out position by the cutting blade54), where said dust is generated by rotation of the cutting blade 54and contact with a workpiece W, may flow in the rearward direction, andconsequently said cutting dust may be collected through the dustcollection port 53 a. As shown in FIG. 6, an arrow 53 b showing therotation direction of the cutting blade 54 may be indicated on the rightsurface side of the cutting blade cover 53.

A swing position (swing angle) of the machining device main body 51 canbe fixed to a lower end position or an arbitrary position during a swingoperation so as to not be further movable in the downward direction byfastening a fixing screw 68 provided on the left surface side of thecutting blade cover 53. The fixing screw 68 is shown in FIG. 11. Byadjusting the swing position of the machining device main body 51 andfixing the swing position in the up-to-down direction by using thefastening screw 68, the protruding length of the cutting blade 54 belowthe contact surface 52 a can thereby be fixed to an arbitrary and/orpredetermined length. Because of this adjustment, the cutting depth ofthe cutting blade 54 with respect to the workpiece W can be adjusted andfixed to an arbitrary and/or predetermined length. As shown in FIG. 11,a cutting depth scale 53 d for indicating the cutting depth of thecutting blade 54 may be provided on the left surface side of the cuttingblade cover 54.

As shown in FIG. 9, the machining device main body 51 may be providedwith the electric motor 60 that serves as the driving source for androtates the cutting blade 54. The machining device main body 51 may alsobe provided with a reduction gear portion 58 that houses a reductiongear train for decreasing rotation output of the electric motor 12 in agear case 58 a, and a handle 70 that a user holds. The electric motor 60may be connected to the left side of the reduction gear portion 58.

A DC brushless motor that is powered by a battery pack 66 (DC powersource) serving as a power source can be used as the electric motor 60.The electric motor 60 may be provided with a stator 60 b that is fixedto a motor case 60 a as well as a rotor 60 c that is rotatably supportedon an inner circumference of the stator 60 b. A sensor PCB 60 gincluding an electromagnetic sensor for detecting a rotation position ofthe rotor 60 c may be attached to the rear surface (left surface) of thestator 60 b in a direction of a motor axis J. A motor shaft 60 d that isjoined to the rotor 60 c may be rotatably supported around the motoraxis J via a right bearing 60 h and a left bearing 60 i. The rightbearing 60 h may be held in the gear case 58 a and the left bearing 60 imay be held in an intermediate partition wall 60 j of the motor case 60a.

A cooling fan 60 f may be attached to the motor shaft 60 d. As shown inFIG. 11, a plurality of intake holes 60 e may be provided on the leftside of the motor case 60 a. When the electric motor 60 is driven, thecooling fan 60 f attached to the motor shaft 60 d may rotatesynchronously with the motor shaft 60 d. Due to the rotation of thecooling fan 60 f, outside air may be introduced into the motor case 60 avia the intake holes 60 e. Outside air which flows into the motor case60 a may flow in the rightward direction (in the direction of the motoraxis J toward the cutting blade 54), cooling the stator 60 b, the rotor60 c and the sensor PCB 60 g, etc. A ventilation hole 60 k may beprovided on the motor case 60 a on the lateral side of the cooling fan60 f (at the front/rear side of the fan 60 f) as shown in FIG. 12.Outside air (motor cooling air) that has cooled the interior of themotor case 60 a may flow into a controller housing 75 via theventilation hole 60 k. Outside air which flows into the controllerhousing 75 may be used for cooling the controller 76, which will bediscussed in detail infra.

Rotation output of the electric motor 60 may be decreased through thereduction gear portion 58 and then transferred to the spindle 59. Thespindle 59 may protrude into the interior of the cutting blade cover 53through an arc-shaped insertion groove hole 53 c provided on the leftside of the cutting blade cover 53. Furthermore, a tip end of thespindle 59 protruding into the interior of the cutting blade cover 53may be attached to the circular cutting blade 54. The center of rotationof the cutting blade 54 may be fixed by use of a cutting blade fixingscrew 59 a that can be firmly fastened and fixed to the tip end surfaceof the spindle 59. The spindle 59 may be rotatably supported by the gearcase 58 a via a right bearing 59 b and a left bearing 59 c.

As shown in FIG. 12, a battery attachment portion 64 may be provided onthe front side of the motor case 60 a. Similarly, a battery attachmentportion 65 may be provided on the rear side of the motor case 60 a. Thebattery attachment portions 64 and 65 may be used for attaching batterypacks 66 at the front or back of the motor case 60 a, respectively. FIG.11 shows a state where the battery packs 66 are removed from the batteryattachment portions 64 and 65. Each of the front battery attachmentportion 64 and the rear battery attachment portion 65 may be configuredsuch that a slide-attachment-type battery pack 66 can be attachedthereto. In more detail, the front battery attachment portion 64 may beprovided with a pair of upper and lower rails 64 a. Furthermore,positive and negative battery terminals may be arranged between the pairof upper and lower rails 64 a. Similarly, the rear battery attachmentportion 65 may be provided with a pair of upper and lower rails 65 a,and positive and negative battery terminals may be arranged between thepair of upper and lower rails 65 a. The battery packs 66 may be attachedby being slid into each of the front and rear battery attachmentportions 64 and 65, respectively, in the rightward direction. On thecontrary, the battery pack 66 may be detached from each of the front andrear battery attachment portions 64 and 65 by being slid in the leftwarddirection while a removal button 66 a provided on the left end of thebattery pack 66 is concomitantly pressed.

A lithium ion battery may be used as the battery pack 66 in which aplurality of lithium ion battery cells are housed in a battery casehaving an approximately hexahedral shape. The battery pack 66 may behighly versatile such that it can be attached to other electric powertools, other than the portable machining device 50. By sliding thehexahedrally-shaped battery pack 66 in the direction of the motor axis Jtoward and away from the cutting blade 54, the battery pack 66 can beattached to and removed from each of the battery attachment portions 64and 65, respectively. When the battery packs 66 are removed from thebattery attachment portions 64 and 65, they can be recharged by adedicated battery charge, such that they can be repeatedly used.

As shown in FIGS. 7 and 12, a residual capacity display portion 62 forshowing residual capacity of the battery backs 66 and a variable speeddial 63 for finely adjusting a rotational speed of the electric motor 60may be provided on the upper surface of the motor case 60 a.

As shown in FIG. 12, a controller housing 75 may be provided on theright side of the rear battery attachment portion 65 at the rear of theelectric motor 60. The controller housing 75 may have a box shapeextending from the rear of the motor case 60 a in the rearwarddirection. As shown in FIG. 11, the controller housing 75 may beconfigured such that when the machining device main body 51 ispositioned at its upper end position, the controller housing 75 extendsapproximately horizontally from the rear of the motor case 60 a in therearward direction along and to the rear of the upper rearmost surfaceof the base 52. Because of this configuration, as shown in FIG. 8, whenthe machining device main body 51 is moved to the lower end position,the rear side of the controller housing 75 may be directedcounterclockwise upward and forward in a tilting manner in the upwarddirection. A controller 76 for mainly controlling the electric motor 60may be housed in the controller housing 75. In the present embodiment,features as to the position of the controller 76 in the controllerhousing 75 are devised, which will be discussed in more detail infra.

The handle 70 that the user holds may have a loop shape straddling theupper portion of the motor case 60 a of the electric motor 60 as well asthe rear upper surface of the controller housing 75. A front portion ofthe handle 70 may be joined to the upper surface of the motor case 60 aand a rear portion of the handle 70 may be joined to the rear uppersurface of the controller housing 75. An inner circumference of thehandle 70 having the loop shape may have a sufficient space (holdingarea S) in a manner such that the user can insert their hand into thearea so as to grip/hold the handle 70. A trigger-type switch lever 73which may be pulled inwards by a user's fingertips may be provided onthe underside of the inner periphery of the handle 70. As shown in FIG.11, a main switch 74 may be housed in the handle 70 at the rear of theswitch lever 73 in a pulling direction of the switch lever 73. When theswitch lever 73 is pulled, the main switch 74 may be switched on,starting to drive the electric motor 60. When the electric motor runs,the cutting blade 54 may begin to rotate.

A front grip 72 may be provided at the front portion of the handle 70.As shown in FIGS. 7, 9 and 10, the front grip 72 may extend from thefront portion of the handle 70 in the leftward direction. The user caneasily move and operate the portable machining device 50 in a morestable manner by holding the handle 70 with one hand and the front grip72 with another hand. A lock off lever 71 may be provided on the uppersurface of the handle 70. When the lock off lever 71 is not in a forwardposition, the switch lever 73 may be locked in an off position so as tonot be able to be pulled. In contrast, when the lock off lever 71 isslid to the forward position with, for example, a thumb of the user'shand that holds the handle 70, the switch lever 73 may be able to bepulled inwards by the user's fingertips.

The controller 76 may have a rectangular plate shape and may house acontrol circuit board in a case having a shallow bottom. The interior ofthe case may be resin molded. The controller 76 may include a controlcircuit for mainly controlling the electric motor 60 and a power supplycircuit. In more detail, the control circuit may include amicroprocessor that transmits a control signal based on positionalinformation of the rotor 60 c that is detected by the sensor PCB 60 g ofthe electric motor 60. Furthermore, the controller 76 may also include adrive circuit composed of FET that switches the current of the electricmotor 60 based on the control signal received from the control circuit.Furthermore, the controller 76 may also include an auto-stop circuitthat interrupts power supply to the electric motor 60 based on adetection result from the battery pack 66 in order to preventover-discharging and over-current conditions.

As shown in FIG. 11, the rectangular flat-shaped controller 76 may behoused in the controller housing 75 in a tiltable manner mainly in theleft-to-right direction. As shown in FIG. 11, in the present embodiment,when the machining device main body 51 is moved to its upper endposition, the controller 76 may be situated so as to be fixedapproximately horizontal in the front-to-rear direction but tiltable inthe left-to-right direction such that the top portion of the controller76 may approach the side of the cutting blade 54 (in a direction inwhich the controller 76 is tilted toward the rightward direction from aright angle with regard to the base 52). Because of this configuration,as shown in FIG. 12, when the machining device main body 51 is moved toits lower end position, the controller 76 may be tilted in thefront-to-rear direction as well as in the left-to-right direction.

Furthermore, when the machining device main body 51 is moved to itslower end position, the entirety of the controller 76 may be situated tobe offset rearwards from a location where the handle 70 (the holdingarea S) extends in the front-to-rear direction. In this way, thecontroller 76 may be arranged to be tiltable in the front-to-reardirection as well as in the left-to-right direction and in theup-to-down-direction without interference. In other words, thecontroller 76 may be tilted in a compound manner. Because of thisconfiguration, the height of the handle 70 may be restricted and at thesame time sufficient holding space (holding capability) can be obtained.

Furthermore, the machining device main body 51 may be supported so as tobe swung in the up-to-down direction about the main body support shaft57 (swing fulcrum) that is located to the rear of the center of rotationof the cutting blade 54 (to the rear of the spindle 59). Furthermore,the controller 76 may be arranged to be offset in the rearward directionwith respect to the main body support shaft 57. Because of thisconfiguration, as shown in FIG. 8, when the protruding length of thecutting blade 54 protruding below the lower surface of the base 52 is atits maximum, the controller 76 may be tilted about the main body supportshaft 57 so as to be displaced counterclockwise in the forward andupward direction as seen from the side view of FIG. 8. Because of thisconfiguration, the space for housing the controller 76 (controllerhousing 75) can be made to be compact in the front-to-rear direction.Furthermore, while being compact, interference of the controller housing75 or the controller 76 with respect to the base 52 is avoided, and alsothe machining device main body 51 is maneuverable to be swung to alarger angle in the upward or left-to-right direction to decrease theprotruding length of the cutting blade 54 protruding below the lowersurface of the base 54.

Furthermore, the holding area S for inserting the user's hand to holdthe handle 70 may be arranged surrounding the handle 70 (mainly aroundthe underside of the lower periphery of the handle 70). The controller76 may be housed in the controller housing 75 in a tiltable manner suchthat the front portion of the controller 76 may overlap with the holdingarea S in the front-to-rear direction and the rear portion of thecontroller 76 may overlap with the holding area S in the up-to-downdirection. Because of this configuration, a necessary and sufficientholding area S to hold the handle 70 (for obtaining a sufficient holdingcapability of the handle 70) can be obtained, while at the same time thecontroller 76 can be arranged in a compact and maneuverable manner.

The machining device main body 51 may be supported so as to be tiltablewith respect to the base 52 via the front support portion 55 and therear support portion 56. As shown in FIG. 10, when the machining devicemain body 51 is situated at a right angle position with respect to thebase 52, the controller 76 may be placed in a tilted manner in thecontroller housing 75 so as to be displaced in a direction approachingthe cutting blade 54 (in the rightward direction) from the down-to-upviewing direction as seen from the rear view of FIG. 10. Because of thisarrangement of the controller 76, the controller housing 75 can be madeto be compact in the left-to-right direction. Furthermore, as shown inFIG. 13, when the machining device main body 51 is tilted in therightward direction, interference of the controller housing 75 withrespect to the base 52 can be avoided and thus this compactconfiguration enables the machining device main body 51 to be tilted ata larger angle in the rightward direction.

Furthermore, as shown in FIG. 8, when the protruding length of thecutting blade 54 protruding below the lower surface of the base 52 is atits maximum, each of the battery packs 66 may be respectively disposedat the front and the rear, respectively, of the electric motor 60 belowthe holding area S of the handle 70. Because of this configuration, whenthe user holds the handle 70, the battery packs 66 do not interfere withthe user's operation.

As shown in FIGS. 9 and 12, the interior of the controller housing 75may be in fluid communication with the interior of the motor case 60 aof the electric motor 60 through the ventilation hole 60 k providedadjacent to the cooling fan 60 f. Because of this configuration, themotor cooling air may flow into the interior of the controller housing75 through the ventilation hole 60 k. The motor cooling air passingthrough the ventilation hole 60 k may be blown out to the controller 76,which can cool the controller 76. The motor cooling air that has cooledthe controller 76 may be further discharged to the outside through anexhaust hole 77 provided on the right side of the controller housing 75,as shown in FIG. 10. In this way, the controller 76 in which heatgeneration sources such as switching elements are mounted can beefficiently cooled by use of sourcing the motor cooling air from thecooling fan 60 f.

In the second embodiment, a rear cover 60 m may be provided on the leftside of the motor case 60 a. A radio communication unit 85 may beprovided on the inside of the rear cover 60 m. A communication adapter86 may be attached to the radio communication unit 85. An adapterinsertion portion 87 for inserting the communication adapter 86 may beprovided on the left end surface of the rear cover 60 m. The adapterinsertion portion 87 may comprise a rectangular hole and penetrate deepin the rightward direction in the motor case 60 a along below theresidual capacity display portion 62. As shown in FIG. 9, an adapterreceiving portion 89 may be incorporated at the innermost part of theadapter insertion portion 87. By inserting the communication adapter 87into the adapter insertion portion 86 to connect to the adapterreceiving portion 89, the radio communication unit 85 may be able toconduct radio communication between the portable machining device 50 andan incidental device such as the dust collector 80 via the communicationadapter 86. The adapter insertion portion 87 may be covered by a cap 88.By inserting the communication adapter 86 into the adapter insertionportion 87 and closing the cap 88, the communication adapter 86 and theadapter receiving portion 89 may be shielded against dust, in adustproof configuration.

The communication adapter 86 may have been previously associated(paired) with a communication adapter of the specific incidental devicesuch as the dust collector 50 such that radio communication can beperformed between the two can take place. In a state where thecommunication adapter 86 is attached to the radio communication unit 85,when the switch lever 73 is switched on to run (start) the portablemachining device 50, the start information from the portable machiningdevice 50 may be transmitted through radio communication to the side ofthe dust collector 80, based on which the dust collector 80 mayautomatically run. As shown in FIG. 8, by attaching a dust collectionhose 81 to the dust collection port 53 a, the dust collector 80 may bean incidental device of the portable machining device 50, and the dustcollector 80 may be in a standby state when powered on. As shown inFIGS. 11 and 12, in the second embodiment, a controller 82 forcontrolling the radio communication unit 85 may be housed at a rearportion of the handle 70. In the second embodiment, the controller 82may be housed at the rearmost portion of the handle 70, within theinterior of the handle 70, on the upper side of the controller housing75. Because of this configuration, due to the flow path of the airflowing in the motor case 60 a towards the controller housing 75, thecontroller 82 for controlling the radio communication unit 85 as well asthe controller 76 for controlling the electric motor 60 can be cooled bysaid air.

As discussed above, the portable machining device 50 may be providedwith a radio communication function to communicate with the dustcollector 80 as an incidental device with regard to, mainly, start andstop operations. Accordingly, the dust collector 80 may automaticallystart/stop in accordance with a start/stop operation of the portablemachining device 50, which can furthermore improve operability andworkability of both the portable machining device 50 and the dustcollector 80.

According to the portable machining device 50 of the second embodimentas discussed above, the communication adapter 86, which is previouslyassociated (paired) with the dust collector 80 serving as the incidentaldevice with regard to the start/stop operation thereof, may beconfigured to be removably housed into the interior of the left endportion of the electric motor 60. Because of this configuration, thedustproof ability as well as convenience of the communication adapter 86can be improved. When there is no need to perform the radiocommunication with the dust collector 80, the communication adapter 86can be easily removed from the portable machining device 1. In thisrespect, communication adapter 86 improves convenience for the user.

Furthermore, the radio communication unit 85 may be provided in closeproximity of the electric motor 60 on the left end side of the electricmotor 60. Because of this configuration, information about start/stopstatus of the electric motor 60 etc. can be accurately and rapidlycommunicated between the dust collector 80 and the communication adapter86 as opposed to the case where the radio communication unit iselsewhere and does not receive the information properly. In thisrespect, reliability of the radio communication unit 85 is improved.

Furthermore, the communication adapter 86 may be configured to beremoved from the adapter insertion portion 87 by being moved away fromthe cutting blade 11 in the leftward direction as shown by the voidarrow showing the detaching direction in FIG. 1. Because of thisconfiguration, attaching and detaching operability of the communicationadapter 86 can be improved.

According to the portable machining device 50 of the second embodimentas discussed above, the controller 76 having the rectangular flat-plateshape may be arranged at the rear of the electric motor 60 and at thesame time to be offset in the rearward direction with respect to theholding area S of the handle 70. Because of this configuration of thecontroller 76, sufficient holding area S (holding capability) can beobtained and at the same time the height of the handle 70 may berestricted.

Furthermore, according to the portable machining device 50 of the secondembodiment, the controller 76 may be housed in the controller housing 75in a compound tilting manner so as to be tilted concomitantly in thefront-to-rear direction, in the up-to-down direction and in theleft-to-right direction. Because of this configuration of the controller76, the controller housing 75 can be made to be compact and as a resultinterference of the controller housing 75 with respect to the base 52can be avoided, and thus the machining device main body 51 is able to beswung at a greater range of angles in the up-to-down left-to-rightdirections.

The first and second embodiments discussed above may be further modifiedwithout departing from the scope and spirit of the present teachings. Inthe first embodiment, the radio communication unit 30, used forconducting radio communication with the dust collector 40 which servesas the incidental device, may be positioned at the front region of thehandle 20, within its interior. In the second embodiment, the radiocommunication unit 85 may be positioned on the left end side of theelectric motor 60. Alternatively, the radio communication unit can alsobe positioned at other locations. For example, in the portable machiningdevice 50 of the second embodiment, which is referred to as a plungecircular saw, the radio communication unit can be positioned at alocation other than on the left end side of the electric motor 60 (athird embodiment).

FIG. 6 shows a plunge circular saw in which a plurality of locationssuitable for positioning the radio communication unit (in a thirdembodiment) are shown in two-dot chain lines. As shown in FIG. 6, theradio communication unit 90 can be positioned at the front of the handle70 within its interior. Further alternatively, the radio communicationunit 91 may also be positioned within the front grip 72. In a case wherethe radio communication unit 90 or 91 is positioned at the front of thehandle 70 or the front grip 72, respectively, the corresponding radiocommunication unit 90 or 91 may need to be positioned on the left sideof the handle 70 or the front grip 72 (on a side opposite to the cuttingblade 11 in the left-to-right direction) such that a removal directionof the radio communication unit 90 or 91 is configured to be leftward inthe detaching direction by the void arrow in FIG. 1, in order to notinterfere with the cutting blade cover 53. With this arrangement, easeof maneuverability in attaching and detaching the communication adaptercan be improved.

Furthermore, as shown by the two-dot chain lines at the bottom rearregion of FIG. 6 and referring to FIG. 7, the radio communication unit92 may be positioned on the left side of the controller housing 75, orthe radio communication unit 93 may be positioned on the rear side ofthe controller housing 75. By arranging the radio communication unit 92or 93 in the controller housing 75 such that the communication adaptermay be removably attached to the respective radio communication unit 92,93, with the respective cap as described, high dust-proofing ability andcooling ability of the controller 76 may be achieved.

In the above-discussed embodiments, cutting devices such as the portablecircular saw, the dust-proofing circular saw or the plunge circular saware exemplified as the portable machining devices. Furthermore, theexemplified radio communication unit may be widely applied to othermachining tools as well, such as aluminum groove-cutting tools, etc.

Furthermore, instead of the exemplified dust collector 40, for example,as shown in FIG. 14, a water injection device 96 may be used as theincidental device that operates synchronously with the portablemachining device via radio communication. FIG. 14 shows a fourthembodiment in which an electric cutter is shown as the portablemachining device 95. The portable machining device 95 of the fourthembodiment may be provided with a tool main body 95 a that houses anelectric motor. A circular cutter 95 b and a semi-circular cover 95 cmay be provided on the front side of the tool main body 95 a. A batterypack 95 d serving as a power source may be attached to the upper portionof the tool main body 95 a. A loop-shaped handle 95 e that the userholds may be provided at the rear of the tool main body 95 a. A pullableswitch lever 95 f may be provided at the upper portion of the innercircumference of the handle 95 e. When the switch lever 95 f is pulledby the fingertips of the user's hand, the electric motor that is housedin the tool main body 95 a may be driven, rotating cutter 95 b. A radiocommunication unit 97 may be provided on the front side of the handle 95e below the battery pack 95 d. A communication adapter may be attachedto the radio communication unit 97.

The water injection device 96 may be a discharge pump that can beactivated by a battery pack 96 a as a power source, and may be connectedto the cover 95 c of the portable machining device 95 via an injectionhose 98. The water injection device 96 may be provided with a handle 96b on the upper thereof that the user holds. The water injection device96 may be provided with an injection tank 96 c at the bottom.Furthermore, the water injection device 96 may be provided with a radiocommunication unit 99 in the vicinity of the battery pack 96 a below thehandle 96 b. A communication adapter may be attached to the radiocommunication unit 99. The other communication adapter that is attachedto the radio communication unit 97 of the portable machining device 95may have been previously associated (paired) with the communicationadapter that is attached to the radio communication unit 99 of the waterinjection device 96.

When the switch lever 95 f is pulled by the fingertips of a user's handto run the portable machining device 95, a starting signal may beemitted from the communication adapter of the radio communication unit97. The communication adapter on the water injection device 96 mayreceive the emitted starting signal via radio communication conducted bythe two radio communication units between portable machining device 95and water injection device 96 to automatically run the water injectiondevice 96. When the water injection device 96 runs, water may besupplied through the injection hose 98 to the cutter 95 b from withinthe cover 95 c. By supplying water toward the cutter 95 b, cutting dustgenerated at the cutting of stone etc. can be prevented from scatteringin the vicinity of the cutting site, and thus a safer workingenvironment can be established. When the portable machining device 95 isstopped, similar to the start signal, a stop signal may be emitted fromthe communication adapter of the radio communication unit 97. Thecommunication adapter on the water injection device 96 may receive thestop signal, via radio communication conducted by the two radiocommunication units between portable machining device 95 and waterinjection device 96, and then the water injection device 96 may stop. Inthis way, water supply to the cutter 95 b may be automatically stopped.

As discussed above, in the portable machining device 95 of the fourthembodiment, incorporating the communication adapter for the radiocommunication into the interior of the machining device main body withan accompanying cap can improve the dust-proof ability of the device.Furthermore, by enabling the communication adapter to be removable fromthe radio communication unit 97, 99, the communication adapter can beeasily removed therefrom to use another portable machining device whenradio communication is not performed, enhancing versatility andinteroperability of device components. In this respect, usability andflexibility of the communication adapter, and by consequence of theradio communication function or the portable machining device 95 and thewater injection device 96, can be improved.

FIG. 14 also shows a portable circular saw as another portable machiningdevice 100. The injection hose 98 may be removed from the waterinjection device 96 and instead another injection hose 101 of theportable machining device 100 may be connected to the water injectiondevice 96. Furthermore, the communication adapter may be removed fromthe then used portable machining device 95 and the removed communicationadapter may be inserted into a radio communication unit 102 of theportable machining device 100. Because of this arrangement, the portablemachining device 100 can also operate synchronously with the waterinjection device 96 by the radio communication with respect to astart/stop operation, etc. In this way, the communication adapter thathas been previously associated (paired) with the communication adapterof the incidental devices can be shared with a plurality of devices.Because of this shared communication adapter, low cost and multiplefunctions can be established with respect to a plurality of the portablemachining devices.

1.-20. (canceled)
 21. A portable machining device, comprising: a basehaving a lower surface configured to contact a material to be cut; amachining device main body which is supported above the base; anelectric motor in the machining device main body; a rotary cutting bladerotated by the electric motor, the rotary cutting blade selectivelyprotruding below the lower surface of the base; a handle arranged inparallel to the rotary cutting blade; and an adapter device (1)configured to communicate with an incidental device and (2) that isdetachably received in an interior of the handle.
 22. The portablemachining device of claim 21, further comprising a support portionconfigured to support the machining device main body and the rotarycutting blade with respect to the base in a tilt angle adjustable mannersuch that the rotary cutting blade can move between an erect position inwhich the rotary cutting blade is substantially perpendicular to thebase and a tilted position in which the rotary cutting blade is at anangle other than 90° with respect to the base; wherein the adapterdevice, when received in the interior of the handle, moves upward withrespect to the base when the rotary cutting blade is moved from theerect position to the tilted position.
 23. The portable machining deviceof claim 21, wherein the adapter device, when received in the interiorof the handle, is closer to the rotary cutting blade than to theelectric motor.
 24. The portable machining device of claim 21, wherein:the rotary cutting blade is rotated about a blade rotation axis; theblade rotation axis intersects the electric motor; and the bladerotation axis is located closer to the base than the adapter device whenthe adapter device is received in the interior of the handle.
 25. Theportable machining device of claim 21, wherein: the rotary cutting bladeis rotated about a blade rotation axis; a dust collection port islocated at a trailing side of the blade rotation axis; and the adapterdevice is disposed on a side of the blade rotation axis opposite thetrailing side when the adapter device is received in the interior of thehandle.
 26. The portable machining device of claim 21, wherein: thehandle includes a recess that receives the adapter device; and therecess has an opening in a direction facing away from the rotary cuttingblade through which the adapter can pass when the adapter is insertedinto and removed from the recess.
 27. The portable machining device ofclaim 26, wherein: the rotary cutting blade is on a first side of thehandle; the opening is a second side of the handle; and the second sideis opposite the first side such that the handle is between the openingand the rotary cutting blade.
 28. The portable machining device of claim21, wherein: the handle comprises a front grip; and the adapter deviceis in the front grip of the handle when the adapter device is receivedin the interior of the handle.
 29. The portable machining device ofclaim 21, wherein: the adapter device is electrically connected to acontroller; and the controller is positioned substantially perpendicularto the base.
 30. The portable machining device of claim 21, wherein theadapter device, when received in the interior of the handle, is abovethe electric motor.
 31. A portable machining device, comprising: a basehaving a lower surface configured to contact a material to be cut; amachining device main body which is supported above the base; anelectric motor in a motor case portion of the machining device mainbody; a rotary cutting blade rotated around a rotational axis by theelectric motor, the rotary cutting blade selectively protruding belowthe lower surface of the base; and an adapter device (1) configured tocommunicate with an incidental device and (2) that is detachablyreceived in the motor case portion.
 32. The portable machining device ofclaim 31, further comprising a support portion configured to support themachining device main body and the rotary cutting blade with respect tothe base in a tilt angle adjustable manner such that the rotary cuttingblade can move between an erect position in which the rotary cuttingblade is substantially perpendicular to the base and a tilted positionin which the rotary cutting blade is at an angle other than 90° with thebase; wherein the adapter device, when received in the motor caseportion, moves upward with respect to the base when the rotary cuttingblade is moved from the erect position to the tilted position.
 33. Theportable machining device of claim 31, wherein: the motor casing portionincludes an aperture configured such that the adapter device can passthrough the aperture; and the aperture is located in a surface of themotor casing portion that faces away from the rotary cutting blade. 34.The portable machining device of claim 31, wherein: the adapter deviceis electrically connected to a controller; and the controller isarranged so as to be tilted in a direction parallel to the rotationalaxis of the of the rotary cutting blade.
 35. The portable machiningdevice of claim 31, wherein: the adapter is electrically connected to acontroller; and the controller is arranged so that an upper portionthereof is closer to the rotary cutting blade than a lower portionthereof.